A little technology
Repair is a profession...
It's also a passion
The different Nikon mounts
Foreword
Since its creation, Nikon has never ceased to improve its camera production and its considerable range of optics.
Here we take a look at the different Nikon frames, especially the Nikon F, which is at the heart of the brand’s reputation.
Let's take a closer look...
It’s the beginning of the story. The Nikon mount is directly inspired by the Contax mount.
This is a double mount, one fixed to the camera body, the other rotatable for focusing.
There are two types of lens for this mount, internal or external, depending on focal length and type of manufacture.
With the internal mount, the focus is originally set on the camera body by a rotary knob and the whole lens rotates.
The unique depth-of-field scale of this mount is designed for a normal focal length of 5cm or 50mm.
With the external mount, when the lens is installed, the depth-of-field scale on the camera body must be set to infinity. Focusing is then done with the lens ring, which remains fixed, a classic operation.
Some Russian Kiev/Contax lenses can be fitted to Nikon S cameras, although there is a risk of scratching the body, as the rear finishing ring is about 1mm wider.
You should also be aware that Kiev/Contax lenses do not have exactly the same helical principle, which can cause focus shifts at the shortest distances.
At wide-angle, the problem disappears thanks to the natural depth of field of these focal lengths.
The Jupiter 12, 35mm f/2.8, is excellent.
Its very prominent rear lens digs deep into the camera and requires attention when changing lenses.
This rear lens, which is very close to the curtains, can also cause the exposure window on negatives to overshoot slightly, reducing the width of the inter-negative spacing.
Don’t suspect that the camera is out of adjustment – we observe exactly the same phenomenon with the Leitz 21mm f/3.4 mounted on Leica M cameras.
From F to Z
The evolution...
The F-mount is completely different from the S-mount.
It is based on the Rectaflex mount.
With the addition of the mirror cage on the Nikon F, the mechanical draft increases and the design of the optics becomes of the retro focus type.
This bayonet mount, created in 1959, has remained unchanged for decades.
The universality of the F-mount was further confirmed by the collaboration of other manufacturers with Nikon.
Particularly during the advent of digital photography, with Kodak using Nikon film cameras and Fuji using its Finepix range.
Many other brands have used or copied the F-mount, which is further proof of Nikon’s excellent ingenuity.
In 1999, Nikon launched the D1 with its 1.6MP sensor, which may seem ridiculous today compared to the 20.8MP of the latest D6 from 2020.
All these digital cameras still use the same F-mount.
Only the recent Z-mount is a radical change.
Reading about the performance of the Z series, particularly the Z9, reinforces my conviction that I made the right choice in the distant days of my youth.
Nikons have always been with me and never let me down. The switch to digital was made by applying the
(not 50 photos for a good one, and remembering that film only had 36 exposures and a single sensitivity from the first to the last frame).
45.7 MP, ISO 64 at 25,600 in normal mode – ISO 32 at 102,400 in extended mode – autofocus detection is guaranteed down to -6.5 Ev, 20 vps in full definition RAW over 1,000 shots, etc etc, putting Nikon once again at the top of the podium.
Nikon mounts often look complex.
By following these developments logically, everything becomes clearer
It is important to remember that the main differences in the F-mount are due to the coupling between the optics and the housings for light measurement.
between the optics and the bodies for light measurement and, subsequently, the developments offering
electronically managed automation. And, of course, developments in optics.
F – AI – AI S – AI P- AF – AF D – AF I – AF G – AF S – AF P
Pre AI or no AI / Ai et Ais
The original Nikon F with a simple roof prism had no light metering system.
Subsequently, several types of viewfinder known as ‘photomic’ (F – T – TN – FTn) gave the Nikon F more functionality.
The original F-mount camera body and lenses remain identical.
Coupling to the body’s light meter is achieved via a fork fixed to the diaphragm ring (rabbit ears).
This coupling allows the maximum aperture of the lenses linked to the viewfinder to be indicated mechanically.
To do this, Nikonists had to move the diaphragm ring back and forth.
This gesture immediately identified a Nikon user. All pre-AI lenses have this fork, a version without a hole.
To find out more, read the full test: Nikon F PHOTARGUS 1969
AI - Aperture Indexing
Mechanical coupling of the lens diaphragm to the camera body light meter, 1977. Ai lenses are easily recognised by their perforated ‘fork’. The F to F4, FM, FE, EL2, F3, F4 and Nikkormat FT3 use the AI metering system but allow non-AI lenses to be adapted, as the lever can be disengaged manually. The F5 could also be fitted with this system, but only by special order: this feature is of very little use to very few cameras.
Mechanical coupling of the lens diaphragm to the body’s light meter, 1977.
Ai lenses are easily recognised by their perforated ‘fork’.
The F to F4, FM, FE, EL2, F3, F4 and Nikkormat FT3 use the AI metering system but allow non-AI lenses to be adapted, as the lever can be disengaged manually.
The F5 could also be fitted with this system, but only by special order: very few of these cameras have this feature.
For the others, coupling the apertures could bend or even break the AI lever.
Pre AI lenses can be upgraded to the AI standard
By replacing the aperture ring. Nikon offered AI rings for a short period when the AI standard first appeared. Each AI kit had a specific part number corresponding to the internal mechanical characteristics of each lens to be adapted. Subsequently, stocks of parts were resold to independent repairers. Most of them are now rare or impossible to find.
AI standard setting - The artisanal method
There is another, less noble and irreversible way of transforming a lens, by filing off part of the diaphragm ring. It is also possible to refine this modification as much as possible by machining in such a way that the protruding part is also useful for entry-level AI cameras and some digital cameras. This part can also be useful for using the DS-2 & DS-12, the diaphragm servo control, an atypical accessory on the Nikon F2.
It should be noted that this modification means that modified models lose their ‘collector’ value, but is an advantage for users.
AI S - Auto Indexing Shutter
The successor to the AI system, 1981. The lens has a rear pin on the aperture ring which indicates to the camera body the value of the chosen aperture. It can be recognised by its double aperture indication ring and the smallest aperture number on the small aperture ring is orange + small cup in the rear mount for FA coupling (focal length indication, two positions: less or more than 135 mm, imposing a fast shutter speed on the automatic system). Nikon transformed its old lenses, and some craftsmen still do. The second crown on the back of the lens can cause exposure metering problems on some older cameras.
The Ais series allows programme mode with FA, F-301, F-501 & F4 cameras that need focal length indication. An ‘Ais’ is still compatible with assisted focus and light metering on F-501, F-601, F-801, F70, F90, F100, F5, F6, and digital D1, D2, D200, Fuji S5 autofocus cameras. On a recent Ai-compatible autofocus camera, there is no difference in aperture priority and centred light metering behaviour, even if the camera is set to matrix metering (except for matrix metering on the F4 and D2, F6, D200, Fuji S5).
Automatic focusing, AF
Autofocus lenses, 1986 on F-501. Equipped with an integrated microprocessor but still compatible with Ai. When using a non-D AF lens on a body manufactured after 96, a limited version of the metering system is used instead of the 3D matrix metering system. The aperture ring must be locked at maximum closure. We can see here that the previous developments have been retained, which increases compatibility.
AF D - Distance
Autofocus lenses, 1986 on F-501. Equipped with an integrated microprocessor but still compatible with Ai. When using a non-D AF lens on a body manufactured after 96, a limited version of the metering system is used instead of the 3D matrix metering system. The aperture ring must be locked at the maximum aperture. It should be noted that previous developments have been retained, which increases compatibility.
AF I - Auto Focus Internal
1992. Large Ai telephoto lenses with internal AF motor.
Replaced by the AF S specification in 1996.
AF I, AF S and AF G lenses have a ‘D’ type chip.
This motorisation has a reputation for being slow, but having owned and carried this 300mm f/2.8 AF I, (it’s terribly heavy), I can say that the AF is extremely fast, almost as fast as the AF Ss.
Only the operating noise is a little higher (but still more discreet than AF and AF D).
AF S - Auto Focus - Silent
1996. Indicated on the lens to the left of Nikkor.
Lenses using Silent Wave Motor technology (integrated focusing motor that does not use the camera body’s built-in autofocus motor) to focus discreetly and quickly. All AFS are AFD. Compatible only with F4, F5, F6, F90, F100, F80, F65, F75 film cameras (not F60/N60, F-801/N8008). Only AFS (and AFI) are unconditionally usable on D40, D50, D60, D3x00, D5x00 digital cameras; most AF G (motorised) are also usable.
It should be noted that, over time, some lenses develop problems. The SWM motor malfunctions and becomes ‘squeaky’.
The logical thing to do is to replace the motor. Nikon’s after-sales service no longer carries out repairs due to a lack of parts.
It is ‘sometimes’ possible to improve operation by disassembling the motor (which is delicate and time-consuming) and cleaning it.
cleaning. But there is no guarantee of success. There are also Chinese suppliers who offer motors on the Internet.
These are still expensive, but there is a risk that they may be recycled, which does not guarantee correct operation.
AF G
2000. These are D-type lenses, except that they have no aperture ring. They can therefore only be controlled by the camera body.
Only autofocus cameras with a control button are able to control G lenses.
Compatible with most film cameras released after the F5 (1996), they operate on other cameras in S (speed priority) and P (programme) modes.
Originally, the first AF G-type lenses were not internally motorised (and the first motorised lenses did have an aperture ring).
Recent models are all internally motorised.
It was also the advent of polycarbonate bayonet mounts
which are highly sensitive to impact.
These bayonets are easy to find on the internet, and are usually made in China.
AF P - Auto Focus Pulse
2016. Indicated on the lens to the left of Nikkor.
Lenses using a stepping motor that allows the focusing group to move more gradually to avoid the jerking and pumping seen in video with traditional AF and AF-S lenses.
Digital cameras from the D5, D750, D610, D600, D5500, D5300 and D3300 are compatible without limitations, but require a firmware update.
The D3400, D5600, D7500 and D500 support AF-P lenses with factory firmware.
Earlier D4, D4S, D3, D3X, D3S, D810, D810A, D800, D800E, Df, D700, D300, D300S, D7200, D7100, D7000, D5200 digital SLR cameras are partially compatible, as they reset focus to infinity each time the exposure meter is switched off (note that this delay can be set in the options).
The evolution continues with the Z frame
Update in preparation